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Background. Evidence has suggested that radiation therapy with a lower dose per fraction may be a reasonable option for the treatment of centrally located non-small cell lung cancer (NSCLC). The aim of this study was to evaluate the safety and efficacy of two proton beam therapy (PBT) protocols for stage I NSCLC and to determine prognostic factors.Material and methods. This study included patients clinically diagnosed with stage I NSCLC. Based on the location of the tumor, one of the two PBT protocols was administered. Patients with peripherally located tumors were given 66 Gy relative biological dose effectiveness (RBE) over 10 fractions (Protocol A) while patients with centrally located tumors were given 80 Gy (RBE) over 25 fractions (Protocol B).Results. Between January 2009 and May 2012, 56 eligible patients were enrolled (protocol A: 32 patients; protocol B: 24 patients). The three-year overall survival (OS), progression-free survival (PFS), and local control (LC) rates were 81.3% [95% confidence interval (CI) 75.9–86.7%], 73.4% (95% CI 67.2–79.6%), and 96.0% (95% CI 93.2–98.8%), respectively. There were no significant differences in outcomes between the two protocols. Late grade 2 and 3 pulmonary toxicities were observed in nine patients (13.4%) and one patient (1.5%), respectively; no grade 4 or 5 toxicities were observed. Sex, age, performance status, T-stage, operability, and tumor pathology were not associated with OS and PFS. Only maximum standardized uptake value (SUVmax; < 5 vs. ≥ 5) was identified as a significant prognostic factor for OS and PFS.Conclusion. Both high-dose PBT protocols achieved high LC rates with tolerable toxicities in stage I NSCLC patients, and SUVmax was a significant prognostic factor.

Nineteen patients with soft tissue sarcoma were treated by a combination modality of hyperthermia and radiation or chemotherapy. There were 26 treatment sites. The size of the tumours ranged from 2.5 x 2 cm to 24 x 26 cm. Hyperthermic treatments were given twice a week, for a total of five to 14 sessions. Twenty-one tumours were treated by hyperthermia combined with radiotherapy, 2 Gy daily, five times a week, for a total of 40-78 Gy. Three tumours were treated by hyperthermia and arterial infusion of adriamycin, 100-120 mg in five or six treatments. For the superficial tumours the complete response rate was 40 per cent, and for the deep-seated tumours 6.2 per cent. Among the 12 tumours with no response, nine in which the treatment was evaluated as effective histologically (necrosis of the tumour) and by X-ray CT findings (development of a prominent hypodensity area) were included. Six cases were studied to correlate the X-ray CT findings, angiography and histological findings before and after hyperthermic treatment. The data were also used to interpret the thermal curve. The increased hypodensity area was roughly proportional to the development of necrosis, but there was one case in which hypodensity was not correlated with the necrosis. On the contrary, even in the contrast-enhanced area around the tumour in which the presence of residual tumour was strongly suspected clinically, no tumour cells were visualized. Clinical evaluation of the effect by size of the tumour can be supplemented by CT findings and histology, but should be cautiously adopted.

Fifty-four patients with 65 superficial malignant lesions were treated by local hyperthermia combined with radiation therapy at the National Cancer Center Hospital, Tokyo. Hyperthermia was delivered with an Aloka Model HMS-020 (2450 MHz) or with a horn-type applicator of BSD-1000 (80-90 MHz). Relatively small tumours, those less than 4 cm in thickness, were treated by using 2450 MHz while 80-90 MHz delivered through the horn-type applicator was used for tumours exceeding 5 cm in thickness. The radiation dose was 4 Gy twice a week or 2 Gy five times a week, the total dose being 40-60 Gy. A total of six to 10 hyperthermia treatments ranging from 40 to 60 min each, with the tumour heated to more than 42.5 degrees C, were given twice a week within 1 h following radiation therapy. Complete response was achieved in 16 of the 30 patients (55 per cent) treated with the 2450 MHz microwave, and partial response in seven others (23 per cent). Tumours treated with the BSD-1000 achieved complete response in 10 out of 33 patients (30 per cent) and partial response in nine others (27 per cent). In five out of nine patients classified as partial responders, however, complete disappearance of tumour cells was noted by post-treatment histological examination. Complete plus partial response rates were thus essentially the same with the Aloka HMS-020 and the BSD-1000, though the rate of complete response was apparently higher with the Aloka unit, probably because it was used on smaller tumours.